Washing method and measurement method of anodic stripping voltammetry method

Abstract

The present invention relates to a washing method and a measurement method of an anodic stripping voltammetry method, wherein the washing conditions are the same as the measurement conditions. According to the washing method, the mixed liquid of a washing liquid and a Zn and / or Cd solution is added to the electrolytic cell of a polarography, and the dissolution peak of the metal to be measured in the mixed liquid is measured; the mixed liquid in the electrolytic cell is changed, and the dissolution peak of the same metal to be measured is measured again, wherein the pollution caused by the metal to be measured exists in the electrolytic cell and the liquid mercury if the height of the later dissolution peak of the metal to be measured is significantly reduced compared to the height of the previous dissolution peak of the metal to be measured; the mixed liquid is changed a plurality of times and the dissolution peak of the same metal to be measured is measured until the height of the later dissolution peak of the metal to be measured is close to or equal to the height of the previous dissolution peak of the metal to be measured so as to indicate the complete cleaning of the electrolytic cell and the liquid mercury; and the measurement is continuously performed, wherein the measurement method uses the same analysis conditions. According to the present invention, the method can be adopted as the definite value analysis method, and can be used for measuring the heavy metal content in seawater or fresh water and other mediums.

Description

Technical field [0001] The invention belongs to the technical field of heavy metal detection, and particularly relates to a washing method and a measuring method of an anode stripping voltammetric analysis method. Background technique [0002] In the past few decades, my country has mainly used flameless atomic absorption spectrophotometry to measure Pb in seawater or freshwater samples. Seawater here refers to seawater at shore, offshore and open seas, excluding seawater at sewage outlets; freshwater refers to Fresh water samples with low salinity, such as unpolluted or lightly polluted water sources, rivers, rivers, and groundwater, do not include fresh water from sewage outlets. In the national standard GB 17378.4-2007 "Marine Monitoring Specification", the detection limit of Pb in seawater measured by flameless atomic absorption spectrophotometry is 0.03μg / L, if converted into a quantitative detection concentration of 0.3μg / L. In the national standard GB / T5750.6-2006, the min...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to solve the problem of poor reproducibility and inaccuracy in measuring the metals to be measured (such as Pb, Cd, In or Cu) in seawater or freshwater samples in the existing standard analysis methods, and to provide a method that combines washing and measurement. Analytical method, which can clean the metal to be tested in the electrolytic cell and liquid mercury, and obtain an analytical method with good reproducibility

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